Additionally from my understanding, RX pilots can only remote pilot fighters and freighters, and R-1s are meant to pilot Capital ships, and the FA-4 Pilot can pilot anything. Is this correct has anyone tried for sure?

If the ship you intend on boarding is docked within the ship that's traveling, And you have the proper pilot droid in the cockpit, then the ship that is traveling will not drop out of hyper or sublight travel by boarding the docked ship, so long as, it (and you), remains docked aboard the transporting craft.

Going on from this question, if the Piloting skill of the PC pilot is different from the skill of a droid that takes control, is the time of flight re-calculated? I suspect not, but just making sure...

Thats false, any droid with Piloting skill will work if the skills match the ships (like Capital piloting for bigger ships), and last time I checked they gave piloting to all R series, not just R-1 I been using for capital for years.

As Lilith stated, as long as the droid had the pilot skill, it will continue to pilot that entity for you. Although I have not tested it as I have no need, the Battle Droid should be able to pilot vehicles when you enter a docked entity.

Has anyone checked whether the T-7 works with hyper yet?
It would be nice to know if the droids with 'not yet implemented status' function as the partially or fully implemented droids do.
It would be a great bonus, especially for newer players to use easily obtained 'CP' droids.